Textile fibre drafting apparatus



Aug. 18, 1959 J. NOGUERA TEXTILE FIBRE DRAFTING APPARATUS Filed May 1, 1958 United States Patent TEXTILE FIBRE DRAFTING APPARATUS Joseph .Noguera, London, England, assign'or "to Casablancas High Draft Company Limited, Manchester, 'Lancashire, England, a British company Application May 1, 1958, Serial No. 732,403

Claims priority, application Great Britain May 2, 1957 10 Claims. (Cl. 19-131) This invention relates to textile fibre drafting apparatus of the well-known Casablancas type employing t-wo superposed endless bands which .are guided over rear driving rollers and separate front tensors and between separate upper and lower cradles which carry the respective tensors, .so that adjoining runs of .the'ban'ds co-operate to guide and control fibres passing therebecradle and a broad platform-like lower tensor, which is interchangeably locatable in the lower cradle, are adapted to inter-engage in the assembled position to determine the permitted maximum tensor spacing at the delivery opening.

Inorder that the invention may be clearly understood and readily carried into effect an embodiment thereof will now be described in detail with reference to the accompanying drawings in which:

Figure 1 is a cross-sectional elevation showing three consecutive roller lines of a drafting apparatus constructed in accordance with the invention, parts of the apparatus which have no bearing on the invention being omitted,

Figure 2 is a plan view of the .two-belt mechanism forming part of the apparatus shown in Figure 1, and

Figures 3, 4 and are respectively a plan, .front elevation and side elevation, to a larger scale, showing the detailed construction of a lower, tensor.

Referring now to the drawings, the invention is applied to a drafting apparatus having three consecutive roller lines, the rear roller line being composed of .upper and lower holding rollers 1 and v2, the intermediate .roller line being composed of upper and lower band driving rollers 3 and 4, whilst the front roller .line is composed of upper and lower drawing rollers 5 and 6. Carried by the respective band driving rollers 3 and 4 are two cooperating superposed endless bands 7 and 8 having adjoining runs between which textile fibres :are guided and controlled during their passage from the holding rollers 1 and 2 to the drawing rollers 5 and 6. 'At'their forward ends the bands 7 and 8 aresupported by separate upper and lower tensors 9 .and "10 which will later be referred .to in more detail.

The two driving rollers 3 and 4 are arranged, in the :usual manner, with their peripheries close together to form a ffirm gripping position or nip .A at the entry end of .the co-operating runs of the superposed bands, whilst .the

tensors guide the front ends of the bands to provide a yielding delivery opening B at the ends of the cooperating runs through which the textile fibres being drafted emerge. These textile fibres are, of course, drawn into the nip A from between the holding rollers Patented Aug. .18 1959 '1 and 2 and are drawn from the delivery opening "B by the drawing rollers 5 and 6.

For the purpose of guiding the bands 7 and 8 laterally there is provided an upper cradle having a pair 5 of laterally spaced side walls 11 and a separatelower cradle having a pair of laterally spaced side walls 12.

The spacing of the upper andlower cradle side walls is substantially the same sothat these cradles will'be approximately in edge to edge relationship when operatively positioned as can be seen from an examination of .Figures 1 and 2. The side walls 12 of the lower cradle are projected downwardly at their forward ends and are joined together at the lower ends of the projections by a transverse tie bar 13. These cradle walls are also joined at their rear ends by a further transverse tie bar 14 and are provided, intermediate the tie :bars, with downwardly directed'registering slots 15 for engaging around necks 4a at oppositeends of the bottom driving roller 4. The upper edge of each lower cradle side wall 12 is upwardly extended at the rear end and the leading edges 16 of these upward extensions are of arcuate 'form to provide seatings 'fornecks 3a on the upper driving roller. In front of these rearward extensions, the upper edges of the lower cradle side walls are shaped so as approximately to follow the contours of the lower edges of the upper cradle side walls as will be later explained. Towards the forward ends of the lower cradle side walls,'the latter'are formed with recesses 17 which open through the upper side wall edges and serve to locate the lower tensor 10. These lower cradle side wall recesses 17,'which are in register, are undercut at their rear ends 17a and terminate, at their forward ends, in upstanding fingers 18.

The lowertensonwhich can be seen-most clearly in Figures 3, 4 and 5, is in the form of a broad platformlike bar member which is arranged to extend across the inside of the lower band 8 'to support the operative band run. This lower band 8 returns around the front or leading edge 10a of'the tensor bar at the-delivery opening B between the bands. The lower tensor bar has a slightly arcuate or convex upper surface in the direction of its breadth (i.e. from the front to the v rear edge) so that theoperative lower band run may be more or less deflected, depending upon the radius of curvature, into a shallow arcuate path in passing over the lower tensor. To locate the lower tensor in the as to seat in 'the respective undercut portions 17a of these recesses. At the forward ends of the lower'tensor side edges, are provided lateral flaps 20 which bear on the tops of the fingers 18 defining the forward ends of recesses 17, these 'flaps 20 being rearwardly and'downwardly extended at 20:: to provide downwardly directed abutment edges for interengaging the forward ends of the upper cradle side walls 11 as will be later explained.

The upper tensor 9 is in the form of a cross-piece which is fixed between the upper cradle'side walls 11 and serves to join these walls rigidly together. The forward edge 9a of this tensor is rounded for the purpose of guid- .ing the front end of the upper belt 7 and the cross-piece is arched orvangled awayfrom the operative run of the upper band as shown.

The rear end edges of the upper cradle side walls '11 have arcuate recesses 11a formed therein for bearing against the upper roller necks 3a at positions opposed to the seatings for the aforesaid upper-roller necks which are provided by the arcuate portions 16 ofthe lower cradle side walls. The front edges of the upper cradle side walls are also recessed to form forwardly projecting hook parts 11b at the lower recess ends which can be engaged under the respective abutment edges of the lower tensor front upper cradle side walls can be hooked under either of two alternative pairs of abutment edges 20b or 200. In this way by making, for example, the pair of abutment edges 20b project downwardly further than the other pair, the size of delivery opening B can be varied, without dismantling or disturbing the apparatus, this serving at the same time also to vary the degree of deflection to which the operative band runs are subjected between the driving rollers and delivery opening. To assist in locating the lower tensor in one or other of its adjustment positions, small projections 21 are provided beneath the front tensor edge for abutting the side faces of the fingers 18 on the lower cradle side walls 12. The upper surfaces of flaps 20 are preferably also marked with appropriate numbers as at 22 which become visible alternatively according to the lateral tensor setting. It is, of course, also possible to provide lower tensors having different curvatures'or shapes to vary the form of band deflection. For further distinguishing different tensors, the latter may be also finished in different colours by various known processes.

In the operation of the apparatus described, the operative runs of the upper and lower bands 7 and 8 will be caused to impinge upon one another resiliently so that the forward end of the upper cradle will always have a tendency to swing upwards about the axis of the rear driving roller 3. As a result, the upper cradle will always tend to lift at the front as far as the abutment edges 20b, 20c on the lower tensor flap extensions will allow. By changing tensors to provide deeper or shallower flap extensions, or by adjusting a two-stage tensor, the upper cradle and thus also the upper tensor can be caused to swing downwardly or upwardly to give a narrower or wider gap at the delivery opening B. By varying the delivery gap whilst the curvature of the lower tensor remains unchanged, the degree of deflection of the operative band runs will also be altered inversely to the size of delivery opening to vary the control exercised on fibres passing therebetween. This follows from the fact that, with a smaller or larger delivery opening, the operative runs of the bands will be pressed more or less firmly against the lower tensor.

Finally, by employing tensors having different forms or curvatures as aforesaid it is possible also to vary the form of the band deflection over a wide range.

To facilitate the changing of a tensor 10, the undercut portions 17a of recesses 17 are given ample depth to allow the bottom tensor to move rearwardly and completely slacken the lower band 8 when the upper band driving roller 3 together with the band 7 and upper cradle, are lifted (in known manner) away from the lower band and cradle to expose the drafting field. The band 8 is, of 7 course, again automatically tightened when the roller 3,

band guide cradle which carries said upper tensor and is adapted for adjustable interengagement with said lower tensor to determine the size of a delivery opening formed by said tensors between adjoining runs of said bands.

2. An assembly as claimed in claim 1 in which said upper and lower cradles'each comprise spaced side walls, the lower cradle side walls being adapted to seat on neck parts of said lower roller and provide rear seatings for neck parts of said upper roller and the upper cradle side walls having rear edges shaped to bear against said upper roller neck parts at locations opposed to said rear seatings.

3. An assembly as claimed in claim 2 in which said lower cradle side walls have registering tensor locating recesses opening through the upper wall edges, said recesses being undercut at their rear ends and terminating in upstanding fingers at their front ends, and said lower tensor 'having rear lateral lugs for engaging the undercut parts of said recesses and lateral front flaps for bearing on the tops of said fingers.

4. An assembly as claimed in claim 3 in which said upper cradle side walls have front edges formed with forwardly and upwardly directed hook parts and said lower tensor flaps have downwardly directed abutment edges under which said hook parts can be engaged.

- 5. An assembly as claimed in claim 4 in which said lower tensor flaps have at least two pairs of abutment edges, the edges of one pair being extended downwardly from the respective flaps further than the edges of the other pair to provide alternative engagement positions for the upper cradle hooks, and in which stops are provided on the lower tensor to co-operate with said fingers in locating the lower tensor with a selected pair of abutment edges in an operative position.

6. An assembly as claimed in claim 5 in which said undercuts in the lower tensor locating recesses are of sufficient depth to allow the lower tensor to move rearwardly and slaeken the lower band when said upper cradle is unhooked.

7. An assembly as claimed in claim 1 in which the upper cradle has side walls connected by said upper tensor, the latter having a rounded leading edge and being arched away from an operative run of said upper band which adjoins said lower band.

8. An assembly as claimed in claim 1 in which said lower tensor has an upper surface which is convex from the front to the rear tensor edge. I

:9. A textile fibre drafting apparatus comprising upper and lower belt driving rollers, a pair of co-operating belts running one over each said roller, a lower belt guide cradle, a front platform-like lower belt supporting tensor interchangeably carried by said lower cradle, an upper front belt supporting tensor and an upper belt guide cradle which carries said upper tensor and is adapted for adjustable hooked engagement with said lower tensor;

10. A drafting apparatus as claimed in claim 5 wherein visual markings are provided on the lower tensor to indicate which pair of abutments is operatively positioned, and wherein projections are provided beneath the leading edge of the lower tensor to bear against sidefaces of the fingers and thereby locate the tensor laterally with one or other pair of abutment edges in operative posltion.

References Cited in the file of this patent UNITED STATES PATENTS I 2,020,483 Truslow Nov. 12, 193s 2,100,139 Honda Nov. 23,1937 2,532,275 Whittaker], Nov. 28, .1950 2,662,249 'Neu 'Dec;'15,'1953 2,677,858 Kuehn et al May 11, 1954 2,717,425 Noguera S ept.-13, 1955 

